Kedar yes Rimula is SS and also Selenia WR. FS has extra edge in startup conditions, combined by better flow for cold climate conditions. Don't makes sense to me these FS oils esp. with the premium they charge. Might as well have SS with shorter change intervals for our climatic conditions. Just my way of thinking.

I am using Motul 4100. Its better than helix hx7, but I am searching for Rimula or Tekma Mega of Motul.
Also to use STP Diesel oil treatment if Rimula or Tekma not found.

Click to expand...

I have used Tekma Mega 15W40 and before that Rimula R4 15w40.
Tekma for 5L pack costs around 1500 and Rimula 5L pack around 1700. For this cost, both are absolute value for money. Initially I used Rimula R4. The engine is smoother than when it was filled up with Selenia 5W40.

Recently I changed Tekma Mega. The engine is a bit noisier. I guess its because I am yet to replace my Air Filter and dirty MAF.

I am currently in the dilemma of going for a CAI/K&N or BMC Air filter. Once I change it I ll update whether the engine noise have reduced.

A guide, for reference only. For harsh Indian conditions, is 5W40 or lower, really needed? @asimpleson your valuable opinion Sir. I am shifting to 10w40 just for its 10000km drain interval. Else even 15w40 would be fine too. Mine's a 68hp petrol.

@puntophile,
With more no. posts comes the tag esperto So not really an expert as you mentioned earlier, more like an keen observer, would like to think of.

Semi-Synths of any grade 5w or 15w work as far as they can flow and do not get effected due to freezing and remaining stagnant. Oils have been recommended 5W by companies also so that they can sustain more climatic changes in cold regions esp. when the cars stand in freezing conditions. Also the problem is especially during startup, when it should be able to provide maximum protection from wear and tear.

Multigrade, meaning two grades in one oil (2 in 1) for cold and hot season is formulated for ease of use of owner so that there is no need to buy seperate oils as was practiced in history. Therefore if you are having cold climate, freezing temperatures, best to use 5W40 or even 0W40, else you can use 10W40 depending on the climatic conditions season wise.

But please change most oils 5W at 10-12k kms or 10W at 7.5k kms intervals to ensure the engines do not run much degraded oils. Also as far as oil is there, the engines do not seize, but that oil needs to flow well which is also an important factor. Else in medium to long run damages can cause engine repairs and replacements.

Also further the viscosity and quality can somewhat from consumer point of view be ensured with HTHS ratings. That can also translate into the durability of oil. HTHS ratings above 3.5 can offer above average protection and those below 3.5 can offer protection with limitations but more fuel economy.

If I may, I would suggest as I have been strongly to most in touch with me, is the use of ZDDP additives in engine oil, for extra protection. One such product is STP oil additive, however there are or could be more such products. The content of this additive has been reduced since older days and it has as per some observers increased the no. of premature failures in engines or engine component damages. There are no guarantees here, but those using have had good experience including engine mechanics who think it makes a certain positive impact. ZDDP is anti-friction material already in oils but lesser in content due to emission and DPF reasons.